The present invention relates to a backlight assembly for a liquid crystal display device. More particularly, the present invention relates to a backlight assembly for a liquid crystal display device, the backlight assembly being used with an image display panel such as a liquid crystal display panel, in which it is possible to easily perform assembly and exchange of lamp units and in which it is further possible to achieve improvements in reliability.
A conventional backlight assembly for a liquid crystal display device shown in FIG. 8 and FIG. 9(a) which is a partial enlarged sectional view seen from a direction of an arrow B in FIG. 8, comprises lamp units 11 serving as light sources, a frame 12 for supporting these lamp units 11, a light-conducting plate 13 made of acrylic resin or the like and optical sheets 14 (diffusion sheet, lens sheet, reflecting sheet, etc.) which are overlapped onto both surfaces of the light-conducting plate 13. The frame 12 comprises a frame main body 12a and a supporting frame 12b laminated onto the frame main body 12a for supporting the lamp units 11 and peripheral portions of the optical sheets 14.
As shown in FIG. 9(b) which is a perspective view of the lamp units 11 including partially omitted portions, each lamp unit 11 comprises a lamp reflector 17, a cold-cathode fluorescent lamp 15 attached within the lamp reflector 17 to serve as a light-emitting source, and lamp rubbers 16 provided on both ends of the cold-cathode fluorescent lamp 15.
In order to enable holding of the lamp units 11 by the frame 12 and easy insertion thereof, each lamp unit 11 is formed with a predetermined clearance C1 over the entire outer periphery of the lamp reflector 17.
However, in the above-described arrangement of the conventional backlight assembly for a liquid crystal display device, unevenness is caused in the clearance C1 between each lamp unit 11 and the frame 12 depending on methods for insertion, and it is difficult to maintain a predetermined clearance. Moreover, in the presence of projections (returns and burrs) at both end portions 17a of the lamp reflector 17 which are formed during processing and molding (see FIG. 9(b)), sliding of the lamp units 11 on the frame 12 will increase contact resistance between the end portions of the lamp reflector 17 and the frame main body 12a to thereby prevent smooth sliding of the lamp units 11. Consequently, there are presented drawbacks that deformations in the frame 12 or the lamp reflector 17 or generation of foreign matters within the lamp reflector 17 occur, and inconveniences in view of assembly and reliability are caused.
The present invention has been made with the aim of solving these problems, and it is an object thereof to provide a backlight assembly for a liquid crystal display device in which it is possible to easily perform assembly and exchange of lamp units and in which it is possible to achieve improvements in reliability.
In accordance with the present invention, there is provided a backlight assembly for a liquid crystal display device comprising lamp units each including a lamp reflector, a lamp portion attached within the lamp reflector and lamp rubbers provided on both ends of the lamp portion, and a frame for holding the lamp units, wherein the lamp units are arranged to include means for maintaining a predetermined clearance between at least end portions of the lamp units and the frame.
It is preferable that the predetermined clearance is approximately 0.1 to 10 mm.
It is preferable that a part of the lamp rubbers of the lamp units projects outward from the end portions of the lamp reflector along axial directions of the lamp reflector and a part of the projecting portions projects out from an outer peripheral surface of the lamp reflector.
It is preferable that at latest one projection is formed on the outer peripheral surface of the lamp reflector.
It is preferable that at least a tip end of the projection is formed in a rounded manner.
It is preferable that the projection is formed by drawing the lamp reflector.
It is preferable that portions which project in the axial direction of the lamp reflector and of which tip ends are folded back inward of the lamp reflector are formed at end portions of the lamp reflector.